Forced-draft stoker



A. P. STRONG FORCED DRAFT STOKER June ,14, 1927. l 1,632,423

Filed Jan, 24, .192s 2 sums-snm 1 me 1% 1927k A P STRONG 1,632,423

FORCED DRAFT s'roman Filed Jan. 24, 192s a sheets-sheet 2 IIIIIIIII frenata June i4, 1927.

ARTHUR IP. STRONG, OF CHGAGO, ILLINOIS.

FORCED-DRAFT STOKLER.

Application inea January sa, 192s. sei-iai no. 614,515,

This invention relates to forced draft .stehe/rs of the type wherein the draft 1s I. supplied to the active grate surface from below and through a plurality of transverse Fig. 1 is a vertical longitudinal sectionall View tlirough a chain grate Stoker constructed in accordance with my invention; 4

Fig. 2 is a transverse sectional view taken on line 22 of Fig. 1; i

Fig. 3 is a fragmentary horizontal sectional view taken on line 3 3 of Fig. 1; and n Fig. 4t is a view of oneof the damper plates for one of the compartments and taken on line i-l of Fig. l. ln the drawings, 1 indicates an endless chain grate operating over drums 2, 2 at the 30 ends of the same in accordance with the usual prac-tice. rlhe space between the upper and lower leads 3, 1l; of the grate is divided into a plurality of draft compartu ments 5, 5 by 'a plurality of transverse members or beams 6, 6. The members 6, 6 are vertically arranged and are laterally spaced apart, 'as shown in Fig. 1, to provide the compartments. The upper lead 3 rests on skids or rails 7, 7 extending longitudinally of the grate and across the several members 6 6. 7The spaces between the skids 7 along the upper ends of the beams 6, 6 are closed by shoes 8. These make air seals for the various compartments 5, 5 along the upper edges of the members G, 6. The latter terminate short of the lower lead 1, and to close the spaces thus provided l provide a'number of shoes 9, 9. These have pivotal connection 0 with the members G, 6 so as to permit droppage carried by the lower lead t to pass thereunder toward the front of the grate.

The lower lead runs on skids or rails 10V supported by transverse channels 11, as shown in Fig. l. There 1s a droppagev collecting plate 12 beneath the skids 10 and shown.

,partment 5 through openings 2O provided below the lower lead llas shown. Shoes 13 are arranged between the skids l() in vertical alignment with the members (S to make air seals under the'lower lead 4 at the sides of 60 the compartments 5. 'lhe memberst extend to and are secured to or otherwise supported by vertical side Vplates la, 14 at the sides of the stolrer, las shown in Figs. 2 and 3. These plates 111 close the ends of the com- 65 partments 5 and extend up to the ledge plates 15, which not only support the sides of the upper lead 3, but also seal the compartments along the upper edges of the plates 14. y

To supply the several compartments 5 with forced draft in accordance with my invention, l -provide in front of the first compartment at the forward end of the stolrer a main supply head 16. This is supported vby the forwardly projecting side webs 17 on the front wall l1S and open throughsaid webs topermit draft supply devices to be connected with said header. Extending throughthe vfirst compartment 5 is a plurality of air conduits 19, 19. These open into the main `air box or headerfl at their front ends andterminate at their rear ends at the transverse member@ dividing the first compartment from the second one. i In extending through the first compartment, the conduits 19 pass through the forward upright member G of`- said lirst compartment, ask

The conduits 19 are preferably triangular 90 in'cross section, as shown in Fig. 2, and are arranged ywith their inclined walls upper` most to shed droppage on the lower lead t. These` conduits 19 openinto the second comfor that purpose in the associated upright member 6. These openings 2O have the same shape as the conduitsp19 so as to register with them'. i ,i It is'the second compartment 5 thatJ re ceives the draft at highest pressure, and. to that end the conduits 19 open directly into it, as shown. The other compartments 5 do not need draft at the high pressure required for the second compartment and therefore 105 may be supplied with draft from the second compartment. l To accomplish this, l provide inthe meer. ber G dividing the lirst compartment from the second one, a plurality of draft openings U0 2l, 21. To control the supplying ofidraft from the second compartment tothe first,

I provide a damper plate 22 Slidably supported on the inner side of said member* 6 by suitably shaped bars 23, 23.` The plate 22 is provided with a plurality of openings 24, 24a of the same size and shape as the openings 20, 21 and arranged so as Vto be broughtinto and out of registerwith thev partments to the rear ofthe second one, Iv

provide the members 6 of such compartments with a plurality of. draft openings 28, 2 8.L These in each of said members 6 are controlled by plates 29, 29 Slidably mounted on the associated member 6 by bars 30, 30, as Shown. The plates 29 areeach provided with a plurality of openings 3l, 3l ofthe same' size and shape as the openings 28 and arranged so as to register with the latter by the movement ofthe plate 29. These plates 29 are also given movement from one side of the Stoker and for that purpose I have providedlinks 32pivoted at their inner ends to the'plates 29 and at their outer ends to hand levers 33ml the outside ofthe wall 1'26. `These links 32`extend through-the wallin the same manner asthe links 2F. y

By the structure shown .and described, the use of 'vertical` conduits at the sides ofthe Stoker to supply draftV to'the several transverse compartments, as heretofore, is avoided, andthe draft supplied to the several compartments from ama-in one. The latter is usually the second compartment from the front of the Stoker', inasmuch as the fuel layer over that compartment is that part of thefuel bedwhich requires ahigh pressure draft to gain the ignition required inthe operation of the Stoker. The other compartments d o not require draft' of such high pressure, and by my invention ,suchV otherv compartments are supplied with 'dra from the main one. The damper plates 22, 29l allow the draft supplied to the various compartments to be controlled, thus enabling the amount'of draft supplied to the various coinpartmentstobe reglilatedto suit the combustion requirements on the various'sections of' the grate.' The transverse beams G', G divide the compartments 5, 5 from one another and are the partition members thereof, while the' draft openings 2l and 28 constitute means placing the compartments in communication with each other; 1 Y

While "Ithave shown and' described herein in* detail a Stoker construction embodying the features of my'invention, it is of course to be understood that the details of construction and arrangement of parts illustrated may be variously changed and modiiied without departing from the spirit and Scope ofl'my invention.

I claim as my invention:

l. In' a. f'orced draft Stoker, the combination with an endless chain grate, of means between the upper and lower grate leads providing a plurality of separate draft compartments opening` upward toward the upper lead and downward toward the lower lead so that the latter may carry droppage from the compartments, said compartments having communication whereby forced draft may be Supplied to all compartments from one of the same,y and means whereby Said draft may be initially supplied to one of said compartments.

2. Ina forced draft Stoker,v the combination with an. endless chain grate, of spaced partition members between the upper and lower grate leads forming a plurality ofseparate draft compartments opening upward toward'tlie upper lead and downwa-rd toward the lower lead so that the latter may carrydroppage from the compartments, said partition members having openings permitting forced draftto be supplied to all the compartments from one of the same, and means at the front of the stokerwhereby said draft may be initially supplied to one of said compartments.

n. In a forced draft Stoker, the combination withv an endless chain grate, of means` between the upper and lower grate leads forming a plurality of separate draft compartments openingupward toward the upper Y lead Aand downward toward the lower lead so that the latter may carry droppage from the compartments, said compartments having communication whereby forced draft may be Supplied to all lthe compartments from one of tlie same, and a draft supply conduit between saidgrate leads at the front ofthe Stoker and'opening into the second compartment by extending through the iirst'one.

ll. In a'forced draft Stoker, the combination with an endless chain grate, of spaced partition members between the upper and lower grate leads forming a plurality of separate draft compartments opening.r upward toward'the upper leadand'downward toward the lower lead so that the latter may` carry, droppage from the compartments, -said partition members extending. transversely across thegrate and having` damper controlledopenings permitting forced draft to be supplied to all of the compartments from one of the same,m eans providing air seals for the compartments between the grate leads and'said membersl` the air seal means along `the lower edges of said members being pivoted shoes bearing against the lower lead, andimeans whereby forced Vdraft may.

be initially supplied to one of said compartments.

5. ln a forced draft Stoker, the combination with and endless chain grate, of spaced partition members between the upper and lower grate leads, forming a plurality of separate draft compartments closed at their ends, said compariments opening upward toward lthe uppa' lead and downward toward the lower lead so that the latter may cari-.y droppage from the compartments, said partition members extending transversely across the grate, a main supply air box between the grate leads in front of the first compartment, and air conduits leading from said air box through the first compartment and opening into the second compartment through the partition member between the two, said compartments having communication with each other through the partition members.

6. In a forced draft stolier, the combination with an endless chain grate, of a plurality of spaced partition members between the upper and lower grate leadsforming a plurality of separate draft compartments opening upward toward the upper lead and downward toward the lower lead so that the latter may carry droppage from the compartments, said partition members e2:- tending tansversely across the grate and having draft openings, means for controlling the passage of draft through said openings, a main supply air box between the grate leads in front of the first compartment, and air duets extending from said air boi; through the lirst compartment and opening into the second through the partition member between the two, said ducts having inclined top walls.

7. ln a forced draft stolrer, the combination with an endless chain grate, of spaced partition members between the upper and lower grate leads forming a plurality of separate draft compartments opening upward toward the upper lead and downward toward the lower lead so that the latter may carry droppage from the compartments, said partition members extending transversely across the grate and provided with a plurality of draft openings, damper plates slidably mounted on said partition members and having openings therein for co-operation with the openings in the partition members for controlling` the passage of draft therethrough, and means whereby forced draft may be supplied to one of said compartments.

8. ln a forced draft Stoker', the combination with an endless chain grate, ofspaced partition members between the upper and lower grate leads forming a plurality of separate draft compartments Vopening upward toward the upper lead and downward toward the lower lead so that carry droppage from the compartments, said partition members extending transversely across the grate and having a plurality of draft openings therein, damper plates slidably mounted en the partition members and provided with openings for co-operation with the openings in the partition membersr for controlling the passage of 4draft therethrough, an air box between the grate leads and in front of the first compartment, and a plurality of air ducts leading from said box to the second compartment by extending through the first compartment, the damper plates of the second compartment having enlarged openings for said duct-s.

ln testimony that l claim the foregoing as my invention, I affix my signature this 20th' day of January, A. D. 1923.

' ARTHUR l). STRONG.

the latter mayV 

